The rolling is a processing method for making a plate material, bar material, tube material, and form material of various section by passing through a metal material of high temperature or normal temperature between rolling rings of the rolling roller (generally, a material excellent in wear-resistant property such as ultra-hard alloy, ceramic, or hard alloy is used).
The rolling roller used for this rolling work, its conventional form is shown in FIG. 1(A) and (B).
That is, it is made by a structure comprising: a shaft 1 including key grooves 5a,6a made to receive keys 5,6 for fixing first and second spacers 3,4 to the shaft 1 which is constant in diameter of portion to be assembled by inserting in turn the first spacer 3, the rolling ring 2 and the second spacer 4, and a thread portion 9 for coupling a ring nut 7 fixing an open end when the first spacer 3, a rolling ring 2, and the second spacer 4 are assembled to the shaft 1 together with the keys 5,6 of key groove 5a,6a sides; the keys 5,6 to be respectively inserted and fixed to the key grooves 5a,6a of the shaft 1; the first and second spacers 3,4 to be fixed respectively to the shaft 1 by the keys 5,6; and a ring nut 7 to be coupled to a thread portion 9 together with an adjusting screw 8.
And, FIG. 2(A) and (B) show another form of conventional rolling roller.
Here, it is made by a means that a shaft portion positioned with the first and second spacers 3,4, and the rolling ring 2 has a tapered taper portion 10, and the first spacer 3, the rolling ring 2 and the second spacer 4 are inserted in turn to the taper portion 10, and thereafter a tapered cylindrical sleeve 11 is forcibly inserted by pressing to inside of those tubes so that the rolling ring 2 is fixed to the shaft 1.
And, FIG. 3(A) and (B) are still other form of conventional rolling roller, and here as in the cases of FIG. 1 and FIG. 2, it is made by a means for fixing the rolling ring 2 to the shaft 1 by inserting in turn a plurality of tray springs 12, first spacer 3, rolling ring 2, second spacer 4 and a ring nut 7 to the shaft 1 having a thread portion 9 and a taper portion 10.
In accordance with a thing of FIG. 1 among the conventional rolling roller as this, as in FIG. 1(B), a multiplicity of adjusting screws 8 tightened to the ring nut 7 are released toward arrow direction so that the rolling ring 2 obtains a large torque when the shaft 1 of the rolling roller for processing a raw material A is rotated by a driving power.
At this moment, the second spacer 4 is pushed toward the rolling ring 2 in an axial direction released with the adjusting screw 8, and as a result, the rolling ring 2 is tightly fixed to the shaft 1 by an axial pressure due to the pushing operation of the second spacer 4.
However, here since a strong axial pressure can be produced to the rolling ring 2, a fixing property with the shaft 1 can be improved, but on the contrary, an excessive axial pressure produced by the adjusting screw 8 can give a unreasonable tensile force to the shaft 1, and the production of this unreasonable tensile force has been caused to make a fatigue and damage of the shaft 1 to be fast.
And, in the case of FIG. 2, a tapered thin cylindrical sleeve 11 is coupled to outer side of the shaft 1 formed with the taper portion 10 whereby a strong anti-pressure is made to the rolling ring 2 so that the rolling ring 2 can be tightly fixed to the shaft 1.
However, here since the anti-pressure of the portion contacted with the sleeve 11 and the shaft 1 is large, when thickness of the rolling ring 2a becomes thinner by an abrasion of the rolling ring 2 during using or a re-grinding, the rolling ring 2 can not overcome the anti-pressure whereby it may be damaged, and therefore there has been a problem for obtaining its structural reliability.
And, a temperature of the rolling roll can not but be risen by a contact with the high temperature rolling material during using, and in this case, a coupling strength change of the rolling ring 2 and the shaft 1 is caused by a diametral expansion of the coupling portion, and therefore there has been a problem to reduce a structural reliability.
And, in the case of FIG. 3, the rolling ring 2 is fixed 1 by using three tray springs 12 and a divided rings 13 to the shaft 1 having the taper portion 10 so as to be able to correct the problem of above described conventional technique, so that appropriate torque force was obtained and simultaneously firm supporting property could be obtained.
However, since this makes to manufacture inner diameter of each constituting part to be tapered, an easiness of its manufacture is difficult to secure, and it has caused a price raising of these parts due to use of relatively many parts.
And, since it is a structure that relatively many number of parts are coupled to the shaft 1, it was difficult thing to exclude a disadvantageous problem also due to a length of the rolling roller itself becomes long and a volume or weight is increased, and other than these, a coupling force weakening between the parts by a temperature change may be caused, and when the rolling ring 2 is damaged unexpectedly, there has been a problem to give a damage directly to the shaft 1.